Unmanipulated haploidentical in comparison with matched unrelated donor stem cell transplantation in patients 60 years and older with acute myeloid leukemia: a comparative study on behalf of the ALWP of the EBMT

Reduced intensity conditioning regimen of fludarabine, busulfan, ATG based haploidentical stem cell transplantation for older or unfit patients

Reduced-intensity conditioning (RIC) regimens allogeneic hematopoietic stem cell transplantation (HSCT) was developed for older patients or those with poor functional status. Haploidentical donor was appropriate alternative donor for patients without matched donors or patients with emergency disease state. However, there was few studies report the outcomes of RIC regimen of anti-thymocyte globulin (ATG) based haploidentical HSCT. The selection of the appropriate RIC regimen based on age and comorbidities in ATG-based haploidentical HSCT remains poorly described. To investigate the safety and efficacy of RIC regimen ATG-based haploidentical HSCT in older or unfit patients. Additionally, to explore the potential factors that impact the prognosis of RIC regimen of ATG-based haploidentical HSCT. We included a retrospective cohort of 63 patients with hematologic malignant diseases who underwent their first RIC haploidentical HSCT from November 2016 to June 2022 at our institutions. The conditioning regimen involved fludarabine (Flu) 30 mg/m²/kg 6 days combined with busulfan 3.2 mg/kg 2 days (Bu2) or 3 days (Bu3). ATG-Fresenius (ATG-F) was administered 10 mg/kg in total, ATG-thymoglobulin (ATG-T) was administered 6 mg/kg in total. The median age of patients in the entire cohort was 60 (32-67) years with a median follow-up of 496 (83-2182) days. There were 29 patients with AML, 20 patients with MDS, and 14 patients with ALL. A total of 32 patients underwent Bu2 RIC haplo-HSCT and 31 patients were treated with Bu3 RIC haplo-HSCT. The 2-year overall survival (OS) and 2-year disease-free survival (DFS) in whole cohort were 67.7% (95% confidence interval [CI], 53.8 - 85.1%) and 61.4% (95% CI, 48.8 - 77.3%) respectively. The cumulative incidence rates of grades II to IV and grades III to IV acute graft-versus-host disease (aGVHD) in whole cohort were 15.8% (95% CI, 4.8 - 19.6%) and 9.7% (95% CI, 0.0 - 11.8%) respectively. The 2-year cumulative incidence of chronic GVHD was 34.0% (95% CI, 18.9 - 46.3%). The 2-year cumulative incidence rates of relapse (IR) and non-relapse mortality (NRM) rates in whole cohort were 27.5% (95% CI, 14.5 - 33.7%) and 11.6% (95% CI, 2.2 - 21.9%) respectively. The probability of 2-year OS were 60.2% (95% CI:42.5-85.3%) in Bu2 and 85.5%(95% CI:73.0-100%) in Bu3 group respectively(P = 0.150). The probability of 2-year DFS were 49.7% (95% CI:33.0-74.8%) in Bu2 and 72.6% (95% CI:55.5-95.5%) in Bu3 group respectively (P = 0.045). The 2-year IR of Bu2 group was significantly higher than Bu3 group (P = 0.045). However, the 2-year NRM were not significantly different between Bu2 and Bu3 group(P > 0.05). In multivariable analysis, RIC regimen of Bu3 had superior OS and DFS than Bu2 group respectively [HR 0.42, 95% CI 0.18-0.98; P = 0.044; HR 0.34, 95% CI 0.14-0.86; P = 0.022]. Besides, RIC regimen of Bu3 had lower IR than Bu2 group [HR 0.34, 95% CI 0.13-0.89; P = 0.029]. The RIC regimen of ATG-based haploidentical HSCT is a safe and effective treatment option for patients who are older or have poor functional status. In particular, a relatively high-intensity pre-treatment regimen consisting of Bu achieves significant improvements in OS and DFS, thus providing more favorable post-transplantation clinical outcomes.

Cellular therapies in older adults with hematological malignancies: A case-based, state-of-the-art review

Cellular therapies, including autologous stem cell transplant (ASCT), allogeneic hematopoietic cell transplantation (alloHCT), and chimeric antigen receptor- (CAR-) T cell therapies are essential treatment modalities for many hematological malignancies. Although their use in older adults has substantially increased within the past decades, cellular therapies represent intensive treatment approaches that exclude a large percentage of older adults due to comorbidities and frailty. Under- and overtreatment in older adults with hematologic malignancy is a challenge and many treatment decisions are influenced by chronologic age. The advent of efficient and well-tolerated newer treatment approaches for multiple myeloma has challenged the role of ASCT. In the modern era, there are no randomized clinical trials of transplant versus non-transplant strategies for patients ≥65 years. Nonetheless, ASCT is feasible for selected older patients and does not result in long-term compromise in quality of life. AlloHCT is the only curative approach for acute myeloid leukemia of intermediate and unfavourable risk but carries a significant risk for non-relapse mortality depending on comorbidities, general fitness, and transplant-specific characteristics, such as intensity of conditioning and donor choice. However, alloHCT is feasible in appropriately-selected older adults. Early referral for evaluation is strongly encouraged as this is the most obvious barrier. CAR-T cell therapies have shown unprecedented clinical efficacy and durability in relapsed and refractory diffuse large B cell lymphoma. Its use is well tolerated in older adults, although evidence comes from limited case numbers. Whether patients who are deemed unfit for ASCT qualify for CAR-T cell therapy remains elusive, but the tolerability and efficacy of CAR-T cell therapy appears promising, especially for older patients. The evidence from randomized trials is strong in favor of using a comprehensive geriatric assessment (CGA) to reduce treatment-related toxicities and guide treatment intensity in the care for solid tumors; its use for evaluation of cellular therapies is less evidence-based. However, CGA can provide useful information on patients' fitness, resilient mechanisms, and reveal potential optimization strategies for compensating for vulnerabilities. In this narrative review, we will discuss key questions on cellular therapies in older adults based on illustrative patient cases.

Peripheral Blood Haploidentical Allogeneic Stem Cell Transplantation in Older Adults with Acute Myeloid Leukemia and Myelodysplastic Syndromes Demonstrates Long Term Survival, Results from Australia and New Zealand Transplant and Cellular Therapies

There is a limited body of evidence for haploidentical hematopoietic stem cell transplantation (haplo-HSCT) in older patients. Previous studies have used a high proportion of bone marrow-derived grafts and a variety of conditioning regimens. In Australia and New Zealand, haplo-HCST is predominantly performed using peripheral blood (PB) with universal use of post-transplantation cyclophosphamide (PTCy). To characterize the outcomes of older recipients undergoing haplo-HSCT for acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Data were collected through the Australasian Bone Marrow Transplant Recipient Registry (ABMTRR) for patients aged 65 or older receiving a PB haplo-HSCT for AML/MDS between January 2010 and July 2020. A total of 44 patients were included in the analysis. The median follow-up time was 377 days. The median age was 68 (range 65-74) with a median Karnofsky performance status of 90. Thirty patients (68.2%) had AML, whereas 14 (31.8%) had MDS. The median donor age was 40. The most common conditioning regimen was nonmyeloablative fludarabine, cyclophosphamide, and total body irradiation (75%); the remainder of the patients received either melphalan- or busulfan-based regimens, and the majority were reduced intensity, with only 2 patients undergoing myeloablative conditioning. All patients received post-transplantation cyclophosphamide and mycophenolate mofetil, with the majority also receiving tacrolimus (90.5%) and the remainder receiving cyclosporine (9.5%). No patients received anti-thymocyte globulin. Neutrophil engraftment was achieved in 97.6% of patients at a median of 18 days, whereas platelet engraftment was achieved in 92.7% of patients at a median of 28 days. The cumulative incidences of cytomegalovirus (CMV) reactivation and CMV disease were 52.5% and 5.1% at 1 year. The incidence of grade 2-4 acute Graft Versus Host Disease (GVHD) was 18.2%. The incidence of chronic GVHD at 2 years was 40.7%, with extensive chronic GVHD occurring in 17.7% of patients. The incidences of relapse and non-relapse mortality (NRM) at 2 years were 8.8% and 20.7% respectively. The leading causes of death were infection (64.7%) followed by relapse (14.2%). The 2-year overall survival was 74%. Relapse free survival and GVHD free, relapse free survival at 2 years was 70% and 48%. Haplo-HSCT using a peripheral blood graft and PTCy GVHD prophylaxis demonstrates long-term disease control with acceptable rates of NRM for older patients with AML/MDS.

Reduced post-transplant cyclophosphamide dose with antithymocyte globulin in peripheral blood stem cell haploidentical transplantation

Post-transplant cyclophosphamide (PT-Cy) is effective for graft-versus-host disease (GVHD) prophylaxis, but it may cause dose-dependent toxicities, particularly in frail patients. Therefore, we compared the outcomes with a reduced PT-Cy total dose (70 mg/kg) to those with the standard PT-Cy dose (100 mg/kg) in haploidentical hematopoietic cell transplantation (HCT) patients aged ≥ 65 years and those with cardiac comorbidities. All consecutive patients with a hematological malignancy receiving peripheral blood stem cells (PBSCs) after a thiotepa-based conditioning with low-dose antithymocyte globulin were included. Thirty-three patients received PT-Cy at 70 mg/kg and 25 at 100 mg/kg. PT-Cy dose reduction did not increase the risk of GVHD and was associated with faster neutrophil and platelet recovery, and lower cumulative incidences of bacteremia (38% versus 72%, p = 0.004) and cardiac complications (12% versus 44%, p = 0.028). At 2 years, GVHD-free, relapse-free survival (GRFS) was higher with the reduced dose compared to the standard dose (60% versus 33%, p = 0.04). In conclusion, reducing PT-Cy total dose to 70 mg/kg is a safe and valid approach for elderly patients and those with cardiac comorbidities underdoing haploidentical HCT with PBSCs and low-dose antithymocyte globulin. The reduced PT-Cy dose was associated with improved hematological count recovery, lower incidence of toxicities, and higher GRFS.

Matched related versus unrelated versus haploidentical donors for allogeneic transplantation in AML patients achieving first complete remission after two induction courses: a study from the ALWP/EBMT

We compared transplants (HSCT) from matched related siblings (MSD) with those from matched 10/10 and mismatched 9/10 unrelated (UD) and T-replete haploidentical (Haplo) donors in acute myeloid leukemia (AML) in first complete remission (CR1) achieved after two inductions, a known poor prognostic factor. One thousand two hundred and ninety-five patients were included: MSD (n = 428), UD 10/10 (n = 554), UD 9/10 (n = 135), and Haplo (n = 178). Acute GVHD II-IV was higher in all groups compared to MSD. Extensive chronic (c) GVHD was significantly higher in UD 9/10 (HR = 2.52; 95% CI 1.55-4.11, p = 0.0002) and UD 10/10 (HR = 1.48; 95% CI 1.03-2.13, p = 0.036) and cGVHD all grades were higher in UD 9/10 vs MSD (HR = 1.77; 95% CI 1.26-2.49, p = 0.0009). Non-relapse mortality was higher in all groups compared to MSD. Relapse incidence, leukemia-free, and overall survival did not differ significantly between donor types. Finally, GVHD-free relapse-free survival was lower in HSCT from UD 9/10 (HR = 1.56, 95% CI 1.20-2.03, p = 0.0009) but not in those from UD 10/10 (HR = 1.13, p = 0.22) and Haplo donors (HR = 1.12, p = 0.43) compared to MSD. In conclusion, in AML patients undergoing HSCT in CR1 achieved after two induction courses 10/10 UD and Haplo but not 9/10 UD donors are comparable alternatives to MSD.

Transplantation Referral Patterns for Patients with Newly Diagnosed Higher-Risk Myelodysplastic Syndromes and Acute Myeloid Leukemia at Academic and Community Sites in the Connect® Myeloid Disease Registry: Potential Barriers to Care

Hematopoietic stem cell transplantation (HCT) is indicated for patients with higher-risk (HR) myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). Age, performance status, patient frailty, comorbidities, and nonclinical factors (eg, cost, distance to site) are all recognized as important clinical factors that can influence HCT referral patterns and patient outcomes; however, the proportion of eligible patients referred for HCT in routine clinical practice is largely unknown. This study aimed to assess patterns of consideration for HCT among patients with HR-MDS and AML enrolled in the Connect® Myeloid Disease Registry at community/government (CO/GOV)- or academic (AC)-based sites, as well as to identify factors associated with rates of transplantation referral. We assessed patterns of consideration for and completion of HCT in patients with HR-MDS and AML enrolled between December 12, 2013, and March 6, 2020, in the Connect Myeloid Disease Registry at 164 CO/GOV and AC sites. Registry sites recorded whether patients were considered for transplantation at baseline and at each follow-up visit. The following answers were possible: "considered potentially eligible," "not considered potentially eligible," or "not assessed." Sites also recorded whether patients subsequently underwent HCT at each follow-up visit. Rates of consideration for HCT between CO/GOV and AC sites were compared using multivariable logistic regression analysis with covariates for age and comorbidity. Among the 778 patients with HR-MDS or AML enrolled in the Connect Myeloid Disease Registry, patients at CO/GOV sites were less likely to be considered potentially eligible for HCT than patients at AC sites (27.9% versus 43.9%; P < .0001). Multivariable logistic regression analysis with factors for age (<65 versus ≥65 years) and ACE-27 comorbidity grade (<2 versus ≥2) showed that patients at CO/GOV sites were significantly less likely than those at AC sites to be considered potentially eligible for HCT (odds ratio, 1.6, 95% confidence interval, 1.1 to 2.4; P = .0155). Among patients considered eligible for HCT, 45.1% (65 of 144) of those at CO/GOV sites and 35.7% (41 of 115) of those at AC sites underwent transplantation (P = .12). Approximately one-half of all patients at CO/GOV (50.1%) and AC (45.4%) sites were not considered potentially eligible for HCT; the most common reasons were age at CO/GOV sites (71.5%) and comorbidities at AC sites (52.1%). Across all sites, 17.4% of patients were reported as not assessed (and thus not considered) for HCT by their treating physician (20.7% at CO/GOV sites and 10.7% at AC sites; P = .0005). These findings suggest that many patients with HR-MDS and AML who may be candidates for HCT are not receiving assessment or consideration for transplantation in clinical practice. In addition, treatment at CO/GOV sites and age remain significant barriers to ensuring that all potentially eligible patients are assessed for HCT.

Outcome after allogeneic stem cell transplantation with haploidentical versus HLA-matched donors in patients with higher-risk MDS

Allogeneic hematopoietic stem cell transplantation remains the best curative option for higher-risk myelodysplastic syndrome. The presence of monosomal karyotype and/or complex karyotype abnormalities predicts inferior survival after allo-SCT in MDS patients. Haploidentical allo-SCT has been increasingly used in acute leukemia (AL) and has similar results as using HLA-matched donors, but data on higher-risk MDS is sparse. We compared outcomes in 266 patients with higher-risk MDS after HLA-matched sibling donor (MSD, n = 79), HLA-matched unrelated donor (MUD, n = 139) and HLA haploidentical donor (HID, n = 48) from 2010 to 2019. Median donor age differed between the three groups (p < 0.001). The overall survival was significantly different between the three groups with a better OS observed in the MUD group (p = 0.014). This observation could be explained by a higher progression-free survival with MUD (p = 0.014). The cumulative incidence of grade 2-4 acute GvHD was significantly higher in the HID group (p = 0.051). However, in multivariable analysis, patients transplanted using an HID had comparable mortality to patients transplanted using a MUD (subdistribution hazard ratio [sHR]: 0.58 [0.32-1.07]; p = 0.080) and a MSD ([sHR]: 0.56 [0.28-1.11]; p = 0.094). MUD do not remain a significant positive predictor of survival, suggesting that beyond the donor-recipient HLA matching, the donor age might impact recipient outcome.

Comparison of haploidentical hematopoietic stem cell transplantation with chemotherapy in older adults with acute myeloid leukemia

Acute myeloid leukemia (AML) outcomes are very poor in older patients. Haploidentical stem cell transplantation (haplo-SCT) helps to achieve long-term survival. However, the benefit of haplo-SCT versus chemotherapy is unclear in older adults with AML. Outcomes were retrospectively compared among patients aged 55‒65 years for chemotherapy consolidation or haplo-SCT for AML in the first complete remission with intermediate to high-risk disease. Forty-six patients who underwent chemotherapy and 38 patients who underwent haplo-SCT were evaluated in the final analysis. Compared with the chemotherapy group, patients in the haplo-SCT group had significantly better overall survival (OS) (74.0% versus 23.9% at 36 months, p = 0.005) and leukemia-free survival (LFS) (74.0% versus 21.6%, p < 0.001). The cumulative incidence of relapse (CIR) was significantly lower in the haplo-SCT group (17.3% versus 75.4%, p < 0.001). Treatment-related mortality (TRM) was similar in the haplo-SCT and chemotherapy groups (7.9% versus 4.8%, p = 0.587). In the multivariate analysis, haplo-SCT was associated with improved OS, LFS, and decreased CIR. Haplo-SCT did not affect TRM. In conclusion, our data suggest that haploidentical transplant may be an alternative to consolidation chemotherapy as post-remission therapy in patients with intermediate or high-risk AML aged 55‒65 years. Further well-designed studies are needed to validate this result.

Reduced post-transplant cyclophosphamide doses in haploidentical hematopoietic cell transplantation for elderly patients with hematological malignancies

Although post-transplant cyclophosphamide (PT-Cy) is effective for graft-versus-host disease (GVHD) prophylaxis, it is associated with toxicities, which might be dose-dependent. We compared the outcomes with PT-Cy at 80 mg/kg to those with PT-Cy at 100 mg/kg in elderly patients undergoing haploidentical hematopoietic cell transplantation (HCT). Inclusion criteria included peripheral blood stem cells, hematological malignancy, and age>65 years (or age>60 years if cardiac event history). Thirty-eight patients received PT-Cy at 80 mg/kg and 55 100 mg/kg, divided in two doses. The cumulative incidences (CI) of acute grade II-IV, acute grade III-IV, and moderate/severe chronic GVHD were 32%, 16%, and 13% with PT-Cy at 80 mg/kg compared to 33%, 13%, and 16% with 100 mg/kg, respectively. In multivariable analysis, reducing PT-Cy dose had no significant impact on GVHD. Neutrophil and platelet engraftments were significantly improved, and CI of BK virus-associated hemorrhagic cystitis was reduced with 80 mg/kg of PT-Cy compared to 100 mg/kg. At 2 years, non-relapse mortality was 16% and 31%, progression-free survival 65% and 49%, overall survival 70% and 56%, and GVHD-free, relapse-free survival 52% and 36% with 80 mg/kg and 100 mg/kg, respectively. Reducing PT-Cy dose to 80 mg/kg is safe and associated with improved hematological recovery and lower CI of hemorrhagic cystitis in elderly patients undergoing haploidentical HCT.

Venetoclax with decitabine versus decitabine monotherapy in elderly acute myeloid leukemia: a propensity score-matched analysis

Venetoclax (VEN) combined with azacitidine (AZA) or decitabine (DEC) has been approved for older adults with acute myeloid leukemia (AML) unfit for intensive chemotherapy based on the pivotal VIALE-A trial. However, this trial only compared AZA + VEN with AZA monotherapy. Therefore, we compared the outcomes of consecutive older adults (65 years or older) with newly diagnosed AML who received DEC (n = 230) or DEC + VEN (n = 74) after propensity score matching to construct a one-to-one matched cohort by the nearest neighbor algorithm. The median overall survival was longer in the DEC + VEN group than in the DEC group (13.4 months vs. 8.3 months, p = 0.01). The median event-free survivals were 8.6 and 5.8 months in the DEC + VEN and DEC groups, respectively (p = 0.02). The response rate (complete response, complete response with incomplete hematologic recovery, and morphologic leukemia-free state) was significantly higher in the DEC + VEN group than in the DEC group (70.3% vs. 24.3%, p < 0.01). The 30-day (2.7% vs. 9.5%, p = 0.17) and 60-day (9.5% vs. 18.9%, p = 0.16) mortality rates did not differ between the two groups, nor did the median hospitalization and transfusion rates (hospitalization: 23 days vs. 21 days, p = 0.20; red blood cells: 3.2 units/month vs. 3.5 units/month, p = 0.73; platelets: 2.7 units/month vs. 2.3 units/months, p = 0.48). Of those who received DEC + VEN and became leukemia-free, 29% underwent allogeneic stem cell transplantation and had excellent survival outcomes (one-year survival: 79.4%; one-year non-relapse mortality: 13.3%). This study is the first to provide real-world evidence that DEC + VEN has superior outcomes to DEC monotherapy.

The Gut Bacteria Dysbiosis Contributes to Chronic Graft-Versus-Host Disease Associated With a Treg/Th1 Ratio Imbalance

Introduction

Dysbiosis of gut bacteria has been discovered in a large number of autoimmune diseases. However, the influence of the gut bacteria in the mice model of chronic sclerodermatous graft-versus-host disease (Scl-GVHD), a disease that resembles an autoimmune disease characterized by chronic inflammation of multiple organs, such as skin, remains elusive. Here, we explore the role of gut bacteria in an Scl-cGVHD mice model.

Methods

We established a mouse model of Scl-cGVHD, collected fecal flora, analyzed the composition, and diversity of intestinal flora using 16S rDNA amplicon sequencing, and detected the proportion of Treg and Th1 cells in splenocytes of Scl-cGVHD mice. To verify the immunoregulatory effect of Scl-cGVHD intestinal flora, we prepared bacterial extracts, co-cultured with splenocytes in vitro, and used flow cytometry to detect T cell differentiation and cytokine secretion.

Results

By examining T-cell differentiation in splenocytes of cGVHD mice, we found that Treg cells were significantly reduced (15.27 ± 0.23 vs. 12.23 ± 0.47, p = 0.0045) and Th1 cells were increased (1.54 ± 0.18 vs. 6.68 ± 0.80, p = 0.0034) in cGVHD mice. Significant differences were observed in the composition and diversity of the gut bacteria in mice with Scl-cGVHD versus without GVHD. Analysis of mice fecal bacteria samples (n = 10, 5 Scl-cGVHD and 5 Non-GVHD) showed significant separation [R = 0.732, p = 0.015, non-parametric analysis (ANOSIM)] in Scl-cGVHD and non-GVHD mice. The abundance of the family and genus Ruminococcaceae bacteria decreased and the family Lachnospiraceae and limited to the species Lachnospiraceae_bacterium_DW17 increased in Scl-cGVHD mice. In vitro results of the cellular level study suggest that the bacteria extracts of gut microbiota from Scl-cGVHD mice modulated the splenic T cells toward differentiation into CD4⁺IFN-γ⁺ Th1 cells (14.37 ± 0.32 vs. 10.40 ± 2.19, p = 0.036), and the percentage of CD4⁺CD25⁺Foxp3⁺ Tregs decreased (6.36 ± 0.39 vs. 8.66 ± 0.07, p = 0.001) compared with the non-GVHD mice. In addition, the secretion of proinflammatory interferon- γ (IFN-γ) cytokine in the supplement of cellular culture was increased (4,898.58 ± 235.82 vs. 4,347.87 ± 220.02 pg/ml, p = 0.042) in the mice model of the Scl-cGVHD group, but anti-inflammatory interleukin (IL)-10 decreased (7,636.57 ± 608.05 vs. 9,563.56 ± 603.34 pg/ml, p = 0.018).

Conclusion

Our data showed the different composition and diversity of gut bacteria in the Scl-cGVHD mice. The dysbiosis of gut bacteria may regulate the differentiation ratio of Treg and Th1 cells, which was associated with Scl-cGVHD.

Clinical Significance of Haplo-Fever and Cytokine Profiling After Graft Infusion in Allogeneic Stem Cell Transplantation From Haplo-Identical Donors

Allogeneic stem cell transplantation from haplo-identical donors (haplo-HSCT) has become a well-established therapeutic option for hematological malignancies. The fever of unknown origin (haplo-fever) early after the infusion of T cell repleted graft, which returned to normal right after post-transplantation cyclophosphamide (PTCy), is a unique clinical feature in patients undergoing haplo-HSCT. In the current study, the characteristics of haplo-fever and cytokine profiles during haplo-fever were retrospectively analyzed in a cohort of 37 patients undergoing T cell repleted haplo-HSCT with PTCy as graft versus host disease (GvHD) prophylaxis. In total, 33 patients (89.2%) developed haplo-fever from day 0 to day +7. Patients with high peak temperatures tended to have a lower incidence of chronic GvHD (cGvHD) (p = 0.07), moderate to severe cGvHD (p = 0.08), and superior GvHD and relapse-free survival (GRFS, p = 0.04). During the haplo-fever, there were significant increases in multiple cytokines, such as interferon gamma, interleukin (IL) 6, IL2, IL2 receptor, IL8, IL10, IL17, and tumor necrosis factor (TNF). The increases in IL2 receptor (p = 0.037) and TNF (p < 0.001) on day +4 were correlated with the lower risk of cGvHD. Increased TNF > 1.8055-fold on day +4 was the best predictive threshold for cGvHD, and was correlated with a lower incidence of cGvHD (p < 0.001), moderate to severe cGvHD (p = 0.003), and superior GRFS (p < 0.001). These observations may reflect the early reactivation of donor T cells after haplo graft infusion, which would potentially be eliminated by PTCy. Further studies with larger independent cohorts of patients are warranted, to clarify the clinical significance of haplo-fever, and day +4 TNF as a potential biomarker to predict GvHD and GRFS.

Haploidentical Stem Cell Transplantation for Acute Myeloid Leukemia: Current Therapies, Challenges and Future Prospective

Haploidentical stem cell transplantation (haplo-SCT), an alternative donor source, offers a curative therapy for patients with acute myeloid leukemia (AML) who are transplant candidates. Advances in transplantation techniques, such as donor selection, conditioning regimen modification, and graft-versus-host disease prophylaxis, have successfully improved the outcomes of AML patients receiving haplo-SCT and extended the haploidentical transplant indictions for AML. Presently, treating de novo AML, secondary AML, therapy-related AML and refractory and relapsed AML with haplo-SCT can achieve comparable outcomes to those of human leukocyte antigen (HLA)-matched sibling donor transplantation (MSDT), unrelated donor transplantation or umbilical cord blood transplantation. For some subgroups of AML subjects, such as patients with positive pretransplantation minimal/measurable residual disease, recent studies suggest that haplo-SCT might be superior to MSDT in decreasing relapse and improving survival. Unfortunately, for patients with AML after haplo-SCT, relapse and infections remain the causes of death that restrict further improvement in clinical outcomes. In this review, we discuss the recent advances and challenges in haplo-SCT for AML treatment, mainly focusing on unmanipulated haplo-SCT protocols. We provide an outlook on future prospects and suggest that relapse prophylaxis, intervention, and treatment, as well as infection prevention and therapy, are areas of active research in AML patients who receive haploidentical allografts.

In-depth time-dependent analysis of the benefit of Allo-HSCT for elderly patients with CR1 AML: a FILO study

allo-HSCT improves outcome of patients aged >60 years with ELN IR and UR AML in CR1.

The benefit of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with acute myeloid leukemia (AML) aged >60 years remains a matter of debate, notably when performed in first complete remission (CR1). To clarify this issue, the French Innovative Leukemia Organization (FILO) performed a 10-year real-world time-dependent analysis. The study enrolled patients between 60 and 70 years of age with AML in CR1 after intensive chemotherapy with intermediate (IR) or unfavorable (UR) risk according to the European LeukemiaNet (ELN) 2010 classification. The impact of allo-HSCT was analyzed through three models: (1) time-dependent Cox; (2) multistate for dynamic prediction; and (3) super landmark. The study enrolled 369 (73%) IR and 138 (27%) UR patients with AML, 203 of whom received an allo-HSCT. Classical multivariate analysis showed that allo-HSCT significantly improved relapse-free survival (RFS; hazard ratio [HR] [95% confidence interval (CI)], 0.47 [0.35-0.62]; P < .001) and overall survival (OS; HR [95% CI], 0.56 [0.42-0.76]; P < .001), independently of the ELN risk group. With the multistate model, the predicted 5-year probability for IR and UR patients to remain in CR1 without allo-HSCT was 8% and 1%, respectively. Dynamic predictions confirmed that patients without allo-HSCT continue to relapse over time. Finally, the super landmark model showed that allo-HSCT significantly improved RFS (HR [95% CI], 0.47 [0.36-0.62]; P < .001) and OS (HR [95% CI], 0.54 [0.40-0.72]; P < .001). allo-HSCT in CR1 is reported here as significantly improving the outcome of fit older patients with AML. Long-term RFS without allo-HSCT is very low (<10%), supporting allo-HSCT as being the best curative option for these patients.

Burden of illness and treatment patterns among patients with peripheral T-cell lymphoma in the US healthcare setting

OBJECTIVE

Limited real-world information exists on the characteristics or treatment patterns of patients with peripheral T-cell lymphoma (PTCL). We reported demographics, treatments and direct healthcare resource utilization (HRU) in a large cohort of US patients newly diagnosed with PTCL.

METHODS

Patients aged ≥18 years with a PTCL diagnosis between January 2011 and December 2016 were identified from the Inovalon MORE² Registry. Continuous medical/pharmacy enrollment 6-months prior to and ≥1-month after the first PTCL diagnosis was required. The main focus of this study was on newly diagnosed patients receiving cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) versus other chemotherapy.

RESULTS

A total 2971 patients with PTCL and chemotherapy information were included in the study; 1706 (57%) received CHOP and 1265 (43%) other chemotherapy. A majority of patients (51.7%) were female; mean (standard deviation) age at index was 61.0 (±16.0), Charlson score was 4.1 (±2.9), and follow-up time was 24.6 (±16.7) months. During the variable follow-up period, HRU was similar for the CHOP and other chemotherapy cohorts; 58.1% and 59.3% had ≥1 all-cause hospitalizations, respectively. The proportion of patients with ≥1 PTCL-related hospitalizations was higher in the CHOP than in the other chemotherapy cohort (40.3% vs. 9.7%, respectively) and mean length of stay was longer (4.6 vs. 3.7 days per patient per month, respectively).

CONCLUSIONS

This retrospective analysis of patients with PTCL revealed high levels of comorbidity and HRU; novel interventions that improve patient outcomes and reduce the HRU burden of PTCL are needed.

Single cord blood transplantation for acute myeloid leukemia patients aged 60 years or older: a retrospective study in Japan

The availability of alternative donor sources could allow elderly patients to receive allogeneic hematopoietic cell transplantation (HCT). We retrospectively evaluated the outcomes of single-unit cord blood transplantation (CBT) in 1577 patients aged ≥60 years with acute myeloid leukemia (AML) in Japan between 2002 and 2017. In total, 990 (63%) patients were not in complete remission (CR) at the time of CBT. A myeloablative conditioning regimen (52%) and calcineurin inhibitor (CI) + mycophenolate mofetil (MMF)-based graft-versus-host disease (GVHD) prophylaxis (45%) were more commonly used. With a median follow-up for survivors of 31 months, the probability of overall survival and the cumulative incidence of leukemia-related mortality at 3 years was 31% and 29%, respectively. The cumulative incidence of non-relapse mortality (NRM) at 100 days and 3 years were 24% and 41%, respectively. The cumulative incidences of grade II-IV and grade III-IV acute GVHD at 100 days and extensive chronic GVHD at 2 years were 44%, 16%, and 14%, respectively. The cumulative incidence of neutrophil engraftment was 80% at 42 days. Results of multivariate analysis indicated that the following factors were significantly associated with higher overall mortality: performance status ≥1, hematopoietic cell transplantation-specific comorbidity index ≥3, adverse cytogenetics, extramedullary disease at diagnosis, and non-CR status at CBT. By contrast, female sex, HLA disparities ≥2, mycophenolate mofetil-based GVHD prophylaxis, and recent CBT were significantly associated with lower overall mortality. In conclusion, single CBT offers a curative option for AML patients aged ≥60 years with careful patient selection.

Haploidentical stem cell transplantation vs matched unrelated donor transplantation in adults with hematologic malignancies: a systematic review and meta-analysis

OBJECTIVES

Haploidentical hematopoietic stem cell transplantation (Haplo-SCT) and matched unrelated donor transplantation (MUD-SCT) are two important options when a matched sibling donor (MSD) is unavailable. Several studies comparing Haplo-SCT and MUD-SCT have reported inconsistent clinical outcomes. Therefore, it is necessary to synthesize the existing evidence regarding outcomes of stem cell transplantations comparing Haplo-SCT with MUD-SCT.

METHODS

We searched for titles of articles in MEDLINE (PubMed), Cochrane library, EMBASE database that compared transplantation with Haplo-SCT versus MUD-SCT. To compare clinical outcomes between Haplo-SCT and MUD-SCT, we performed a meta-analysis of 17 studies and reported the pooled odd ratios (OR) of 6 endpoints including overall survival (OS), progression free survival (PFS), non-relapse mortality (NRM), relapse rate (RR), acute graft-versus-host disease (aGVHD) and chronic graft- versus-host disease (cGVHD).

RESULTS

We found that Haplo-SCT was associated with a comparable OS (pooled OR of 0.99, 95% Confidence Interval (CI) 0.86-1.14), PFS (OR 1.00, 95% CI 0.88-1.15), NRM (OR 0.83, 95% CI 0.65-1.04) and RR (OR 1.08, 95% CI 0.95-1.22) compared to MUD-SCT. We also found a significantly decreased risk of aGVHD (OR 0.74, 95% CI 0.62-0.88) and cGVHD (OR 0.50, 95% CI 0.38-0.66) in Haplo-SCT group.

CONCLUSION

Results of this meta-analysis demonstrates that Haplo-SCT achieves comparable clinical outcomes compared to MUD-SCT in terms of OS, PFS, TRM and RR, but is better than MUD-SCT in terms of decreased aGVHD and cGVHD risk. Haplo-SCT is a valid option for patient needing urgent transplantation.

Comparative Efficacy and Clinical Outcomes of Haploidentical Stem Cell Transplantation to Other Stem Sources for Treatment in Acute Myeloid Leukemia and Myelodysplastic Syndrome Patients: A Systematic Review and Meta-Analysis

The use of allogeneic hematopoietic stem cell transplantation (HSCT) is recommended during the first complete remission of acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS). However, only 30% of these cases have fully matched sibling donors (MSDs). Alternatively, matched unrelated donors (MUDs) and haploidentical (haplo) donors from first-degree relatives increase the access to transplantation, with some reported differences in outcomes. The current systematic review and meta-analysis was conducted with the aim of summarizing the results of those studies to compare the efficacy and toxicity of MSD-HSCT and MUD-HSCT versus haplo-HSCT for patients with AML or MDS. Articles published before September 15, 2018, were individually searched for in two databases (MEDLINE and EMBASE) by two investigators. The effect estimates and 95% confidence intervals (CIs) from each eligible study were combined using the Mantel–Haenszel method. A total of 14 studies met the eligibility criteria and were included in the meta-analysis. The overall survival rates were not significantly different between the groups, with pooled odds ratios of the chance of surviving at the end of the study when comparing haplo-HSCT to MSD-HSCT and comparing haplo-HSCT to MUD-HSCT of 0.85 (95% CI: 0.70 to 1.04; I² = 0%) and 1.12 (95% CI: 0.89 to 1.41; I² = 33%), respectively. The pooled analyses of other outcomes also showed comparable results, except for the higher grade 2 to 4 acute graft-versus-host disease (GvHD) for patients who received haplo-HSCT than those who received MSD-HSCT, and the better GvHD-free, relapse-free survival and the lower chronic GvHD than the patients in the MUD-HSCT group. These observations suggest that haplo-HSCT is a reasonable alternative with comparable efficacy if MSD-HSCT and MUD-HSCT cannot be performed. Nonetheless, the primary studies included in this meta-analysis were observational in nature, and randomized-controlled trials are still needed to confirm the efficacy of haplo-HSCT.

Young haploidentical donor versus fully matched elderly donor: An observational study on patients aged 50 years or older underwent hematopoietic progenitor cells transplantation

INTRODUCTION

Stem cell transplantation has been a therapeutic option for increasingly older patients but the search for the donor is an additional question in this context. Currently the ideal donor is a sibiling with fully compatible human leukocyte antigens, but when it is an elderly patient there is a high probability that this donor is also elderly, and the donor age has been related to worse outcomes and the possible comorbidities may render the donor ineligible.

OBJECTIVE

To compare, in patients aged 50 years or older, the overall survival of patients whose donor had haploidentical HLA compatibility and under 50 years of age ("young" donor) versus patients whose donor had a total HLA compatibility and 50 years of age or older ("elderly" donor).

METHODS

This is a consecutive retrospective descriptive observational epidemiological study. All patients were treated during the period from January, 2010 to April, 2019. Overall survival of patients 50 years of age and older was the primary outcome of the study.

RESULT

We included 53 patients. In the multivariate analysis we found no statistically significant difference in overall survival between patients whose donor had fully HLA compatible aged 50 years and older and patients whose donor had haploidentical HLA compatible and aged up to 50 years (p = 0.135).

CONCLUSION

The results obtained in the study show that for patients aged 50 years or older, a donor with haploidentical human leukocyte antigen compatibility and age below 50 years can be chosen without impairing overall survival.

Hematopoietic Cell Transplantation in the Treatment of Newly Diagnosed Adult Acute Myeloid Leukemia: An Evidence-Based Review from the American Society of Transplantation and Cellular Therapy

The role of hematopoietic cell transplantation (HCT) in the management of newly diagnosed adult acute myeloid leukemia (AML) is reviewed and critically evaluated in this evidence-based review. An AML expert panel, consisting of both transplant and nontransplant experts, was invited to develop clinically relevant frequently asked questions covering disease- and HCT-related topics. A systematic literature review was conducted to generate core recommendations that were graded based on the quality and strength of underlying evidence based on the standardized criteria established by the American Society of Transplantation and Cellular Therapy Steering Committee for evidence-based reviews. Allogeneic HCT offers a survival benefit in patients with intermediate- and high-risk AML and is currently a part of standard clinical care. We recommend the preferential use of myeloablative conditioning in eligible patients. A haploidentical related donor marrow graft is preferred over a cord blood unit in the absence of a fully HLA-matched donor. The evolving role of allogeneic HCT in the context of measurable residual disease monitoring and recent therapeutic advances in AML with regards to maintenance therapy after HCT are also discussed.

Haploidentical HSCT with post transplantation cyclophosphamide versus unrelated donor HSCT in pediatric patients affected by acute leukemia

T-cell replete hematopoietic stem cell transplantation (HSCT) from a haploidentical donor followed by high doses of cyclophosphamide has been demonstrated to provide the best chances of a cure for many children in need of an allograft but who lack both a sibling and an unrelated donor. In this study we retrospectively compared the outcome of pediatric patients undergoing T-replete haploidentical HSCT (Haplo) for acute leukemia with those undergoing transplantation from unrelated HLA-matched donor (MUD) and HLA mismatched unrelated donor (MMUD) from 2012 to 2017 at our Center. Both univariable and multivariable analyses showed similar 5-year overall survival rates for MUD, MMUD, and Haplo patients: 71% (95% CI 56-86), 72% (95% CI 55-90), and 75% (95% CI 54-94), respectively (p = 0.97). Haplo patients showed reduced event-free survival rates compared to MUD and MMUD patients: 30% (95% CI 12-49) versus 70% (95% CI 55-84) versus 53% (95% CI 35-73), respectively (p = 0.007), but these data were not confirmed by a multivariable analysis. Non-relapse mortality (NRM) and relapse incidence (RI) were similar for the three groups. Therefore, our data confirm that Haplo is a suitable clinical option for pediatric patients needing HSCT when lacking both an MUD and an MMUD donor.

Haploidentical stem cell transplantation (HaploSCT) for patients with acute leukemia-an update on behalf of the ALWP of the EBMT

Allogeneic stem cell transplantations (alloSCT) from haploidentical (>2 HLA mismatch) donors (HaploSCT) are constantly increasing in Europe. From 2005 to 2015 numbers of HaploSCT increased by close to 300%. In parallel, there is a major shift from T deplete (CD34+ megadose) to T replete (non-T deplete) HaploSCT. Graft versus host disease (GVHD) prophylaxis also changed from CD34+ cell purifications to anti-thymocyte globulin (ATG) and lately to post-transplantation cyclophosphamide (PTCy). Novel conditioning regimens have been developed incorporating novel drugs and innovative approaches. Results are persistently improving and currently, registry-based and single-center studies showed no statistical significance difference in transplantation outcome between HaploSCT to alloSCT from unrelated donors and even from HLA-matched sibling donors, although the numbers of those studies are small and the lack of randomized studies available so far. HaploSCT have several advantages and such as the possibility to choose between different potential donors. Parameters to consider in the Haplo donor selection are age, gender, kinship, ABO blood group, CMV status, non-shared HLA Haplotypes and killer cell immunoglobulin-like receptor (KIR). Future goals are to further decrease transplant-related mortality currently mainly due to infection complications and reduce relapse rates especially in patients with high-risk acute leukemia.

Haploidentical related donor vs matched sibling donor allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia and myelodysplastic syndrome aged over 50 years: A single-center retrospective study

Allogeneic hematopoietic stem cell transplantation (allo‐HSCT) is a potentially curative therapeutic option for patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). Increasing data suggest that haploidentical donor (HID) transplantation achieve comparable outcomes with HLA‐matched sibling donor (MSD) in adult AML/MDS. This retrospective study compared the outcomes of AML or MDS patients age ≥50 years underwent HID and MSD transplantation. One hundred and fifty‐six patients were enrolled in this study, including 75 HID and 81 MSD transplantation. The 100‐day cumulative incidence of II‐IV° acute graft‐versus‐host disease (GVHD) was 33.3 ± 5.4% vs 22.2 ± 4.6%, respectively, in HID and MSD groups (P = .066), and III‐IV° acute GVHD was not significantly different between two groups (5.3%±2.6% vs 6.2%±2.7%, respectively, P = .823). The 2‐year cumulative incidence of limited and extensive chronic GVHD was not statistically different in HID and MSD groups (20.9 ± 5.5% vs 18.9 ± 4.8% and 13.0 ± 4.7% vs 19.7 ± 5.0%, P = .889 and P = .269, respectively). The 2‐year cumulative incidences of relapse (27.0 ± 5.6% vs 22.7 ± 5.1%, P = .509), 2‐year overall survival (63.0 ± 5.8% vs 66.7 ± 5.4%, P = .454), 2‐year transplant‐related mortality (17.2 ± 4.6% vs 17.4 ± 4.4%, P = .847), 2‐year progression‐free survival (59.3 ± 5.8% vs 64.5 ± 5.4%, P = .437), 2‐year GVHD‐free relapse‐free survival (42.6 ± 5.9% vs 40.9 ± 5.6%, P = .964) were not significantly different in the two groups. The present data showed equivalent outcomes in AML or MDS patients age ≥50 years underwent HID and MSD transplantation.

Haploidentical Hematopoietic Stem Cell Transplantation Followed by 'Post-Cyclophosphamide': The Future of Allogeneic Stem Cell Transplant

Allogeneic hematopoietic cell transplant (Allo-HCT) is a potentially curative therapy for many malignant and nonmalignant hematological diseases. However, a suitable human leukocyte antigens (HLAs)-matched donor may not be available when the patient is in urgent need of a stem cell transplant. This challenge has been ameliorated to a large extent by the introduction of haploidentical donors. This type of donor shares one HLA haplotype with the recipient. Therefore, a patient's full sibling has a 50% chance of being haploidentical and a patient's biologic parents and children will all be haploidentical, thus providing an immediately accessible, motivated donor for almost every recipient. Haploidentical transplants previously incurred prohibitively poor outcomes, preventing their widespread use. However, several recent advances have dramatically improved the results, making them a more viable donor source. In this review, we discuss different types of donors used for Allo-HCT with a particular focus on the use of haploidentical donors and their future potential.

The effect of donor type on outcomes in adults with acute myeloid leukemia after reduced-intensity hematopoietic peripheral blood cell transplant - a retrospective study

We retrospectively analyzed outcomes in patients with acute myeloid leukemia (AML) receiving reduced-intensity conditioning (RIC) hematopoietic stem cell transplants (HCT) from a peripheral blood (PB) source. We identified 46 haploidentical HCT (haplo), 59 matched unrelated donor HCT (MUD), and 40 matched related donor HCT (SIB) patients at a single institution. Haplo had improved overall survival (OS) when compared to MUD, HR 2.03 (P = 0.01) but not SIB, HR 1.17 (P = 0.61). There were no differences in relapse rates or treatment-related mortality (TRM). Haplo had higher rates of acute graft-versus-host disease (GVHD) grade II-IV at day 180 than MUD (44% vs. 25%, P = 0.03) and SIB (44% vs. 13% P < 0.01). Rates of acute GVHD III-IV and chronic GVHD were similar among the groups. Haplo had slower engraftment rates compared to MUD with neutrophil engraftment at 87% vs. 93%, (P < 0.01) and platelet engraftment at 59% vs. 86%, (P < 0.01) at 28 days. Although patients receiving haplo had higher acute GVHD II-IV and slower engraftment, they did not have increased TRM. These data may suggest that patients receiving haplo have improved OS compared to MUD for AML patients receiving RIC transplants. This should be confirmed using a larger cohort.

Alternative donor transplantation for acute myeloid leukemia in patients aged ≥50 years: young HLA-matched unrelated or haploidentical donor?

We sought to study whether survival after haploidentical transplantation is comparable to that after matched unrelated donor transplantation for 822 patients aged 50-75 years with acute myeloid leukemia in first or second complete remission. One hundred and ninety-two patients received grafts from haploidentical donors (sibling 25%; offspring 75%) and 631 patients from matched unrelated donors aged 18-40 years. Patients’ and disease characteristics of the two groups were similar except that recipients of matched unrelated donor transplantation were more likely to have poor risk cytogenetics and more likely to receive myeloablative conditioning regimens. Time from documented remission to transplant did not differ by donor type. Five-year overall survival was 32% and 42% after haploidentical and matched unrelated donor transplant, respectively (P=0.04). Multivariable analysis showed higher mortality (hazard ratio 1.27, P=0.04) and relapse (hazard ratio 1.32, P=0.04) after haploidentical transplantation, with similar non-relapse mortality risks. Chronic graft-versus-host disease was higher after matched unrelated donor compared to haploidentical transplantation when bone marrow was the graft (hazard ratio 3.12, P<0.001), but when the graft was peripheral blood, there was no difference in the risk of chronic graft-versus-host disease between donor types. These data support the view that matched unrelated donor transplant with donors younger than 40 years is to be preferred.

How we perform haploidentical stem cell transplantation with posttransplant cyclophosphamide

HLA-haploidentical hematopoietic stem cell transplantation is now one of the most commonly employed alternative donor techniques, with most centers applying T-cell-replete strategies such as that developed by the Baltimore group using high-dose posttransplant cyclophosphamide. HLA-haploidentical hematopoietic stem cell transplantation using posttransplant cyclophosphamide is associated with low rates of severe graft-versus-host disease and nonrelapse mortality and does not require graft manipulation or storage, which results in a low graft acquisition cost. Its remarkable safety when used with reduced-intensity conditioning has been demonstrated in patients up to 75 years old with outcomes similar to those of patients in their 50s. Several large, registry-based retrospective studies have confirmed the efficacy of HLA-haploidentical hematopoietic stem cell transplantation with posttransplant cyclophosphamide, achieving results comparable to those of HLA-matched hematopoietic stem cell transplantation. In this article, we describe our approach to this rapidly available and clinically simple platform and address some of the key clinical questions associated with its use.

What have we learned from transplanting older patients?

Aggressive curative therapies have now been extended to patients older than 65 years, a fast-growing segment of the population. As the number of allogeneic transplants in patients older than age 65 is increasing, attention is now focused on improving outcomes in this group. This paper discusses important aspects of allogeneic transplant in the older patient, focusing on donor and patient selection, choice of conditioning regimen and graft source, and the importance of timely access to a transplant center.

How we perform haploidentical stem cell transplantation with posttransplant cyclophosphamide

HLA-haploidentical hematopoietic stem cell transplantation is now one of the most commonly employed alternative donor techniques, with most centers applying T-cell-replete strategies such as that developed by the Baltimore group using high-dose posttransplant cyclophosphamide. HLA-haploidentical hematopoietic stem cell transplantation using posttransplant cyclophosphamide is associated with low rates of severe graft-versus-host disease and nonrelapse mortality and does not require graft manipulation or storage, which results in a low graft acquisition cost. Its remarkable safety when used with reduced-intensity conditioning has been demonstrated in patients up to 75 years old with outcomes similar to those of patients in their 50s. Several large, registry-based retrospective studies have confirmed the efficacy of HLA-haploidentical hematopoietic stem cell transplantation with posttransplant cyclophosphamide, achieving results comparable to those of HLA-matched hematopoietic stem cell transplantation. In this article, we describe our approach to this rapidly available and clinically simple platform and address some of the key clinical questions associated with its use.

Improved survival after offspring donor transplant compared with older aged-matched siblings for older leukaemia patients

Donor selection for older leukaemia patients undergoing haematopoietic cell transplant (HCT) is not well defined: outcomes might be improved with a younger offspring donor rather than an older human leukocyte antigen (HLA)-matched sibling donor (MSD). We extended our multicentre dataset. A total of 185 acute leukaemia patients (≥ 50 years) transplanted in first complete remission who received HCT from offspring (n = 62) or MSD (n = 123) were included. A 1:1 ratio matched-pair analysis was performed. We were able to match 54 offspring with 54 MSD patients. Outcomes were compared between the two matched-pair groups. The cumulative incidence of grade II/IV acute graft-versus-host disease (GVHD) (26% vs. 35%; P = 0·23) and chronic GVHD (37% vs. 24%; P = 0·19) was comparable between groups (MSD vs. offspring). The lower three-year transplant-related mortality (9% vs. 26%; P = 0·023) and relapse incidence (6% vs. 17%; P = 0·066) resulted in higher overall survival (85% vs. 58%; P = 0·003) and leukaemia-free survival (LFS) (85% vs. 56%; P = 0·001) in offspring HCT compared with that in MSD HCT. These data might favour a young offspring over an older MSD in patients >50 years. The current analyses confirm that non-HLA donor characteristics, such as kinship and donor age, rather than HLA disparity, predominantly influence survival in older acute leukaemia patients.

Haploidentical Transplantation with Post-Transplant Cyclophosphamide versus Unrelated Donor Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis

Hematopoietic stem cell transplantation (HSCT) is the standard treatment for patients with high-risk hematologic malignancies. Only approximately 25% of siblings are HLA-matched, and thus alternative donors-unrelated or haploidentical-are usually the only options available. This meta-analysis aimed to compare haploidentical HSCT with post-transplantation cyclophosphamide and unrelated donor (URD) HSCT. We searched the PubMed and Cochrane databases for pertinent studies indexed between 2008 and 2018. Twenty observational studies (with a total of 1783 haploidentical HSCT recipients and 6077 URD HSCT recipients) were included. Results for overall survival, graft-versus-host disease (GVHD), nonrelapse mortality (NRM), and relapse incidence were pooled. Measures of association used were hazard ratios and risk differences. The median age was 51 years for haploidentical transplant recipients and 52 years for URD transplant recipients. Peripheral blood stem cell (PBSC) grafts were more frequent in the URD transplant recipients (85%) than in the haploidentical transplant recipients (31%). Overall survival was not different between the 2 groups. NRM was lower for haploidentical transplantation. All forms of GVHD (acute grades II-IV and III-IV and moderate, severe, and extensive chronic) were lower with haploidentical donor HSCT. The risk of chronic GVHD was fairly proportional to the differential use of PBSC grafts across studies, however. All included studies were retrospective, representing the major limitation of this meta-analysis. In conclusion, haploidentical HSCT for hematologic malignancies achieved the same overall survival as URD HSCT, with a lower incidence of GVHD and NRM. The increased frequency of PBSC use in the unrelated donor group could partially explain the higher cGVHD rate. Haploidentical transplantation with post-transplantation cyclophosphamide should strongly be considered as the first option for adult patients with hematologic malignancies who do not have matched sibling donors in experienced centers. This systematic review has been registered at PROSPERO (65790).

Prophylaxis and treatment of relapse after haploidentical stem cell transplantation: What is known vs unknown?

In recent years, the human leukocyte antigen-haploidentical stem cell transplantation (haplo-SCT) approach is an attractive option for patients who require transplantation, but relapse is still the main reason that affects the curative effect of transplantation. Some studies have shown that haplo-SCT is superior to sibling or unrelated matching donor transplantation in preventing leukemia relapse after transplantation. In this review, we discussed the known and unknown aspects of relapse post haplo-SCT. Encouragingly, haplo-SCT experienced lower or similar incidence of relapse. But there is currently a lack of multicenter prospective studies evaluating the outcomes of different haplo-SCT strategies. The combination of common prophylactic strategies and pre-emptive interventions might help prevent relapse after transplantation. Novel methods such as target drugs therapy and chimeric antigen receptor T cell therapy may be useful in treatment of relapse.

The European Society for Blood and Marrow Transplantation (EBMT) consensus recommendations for donor selection in haploidentical hematopoietic cell transplantation

The number of HLA-haploidentical hematopoietic cell transplants continues to increase worldwide due to recent improvements in outcomes, allowing more patients with hematological malignancies and non-malignant disorders to benefit from this procedure and have a chance to cure their disease. Despite these encouraging results, questions remain as multiple donors are usually available for transplantation, and choosing the best HLA-haploidentical donor for transplantation remains a challenge. Several approaches to haploidentical transplantation have been developed over time and, based on the graft received, can be grouped as follows: T-cell depleted haploidentical transplants, either complete or partial, or with T-cell replete grafts, performed with post-transplant cyclophosphamide-based graft-versus-host disease (GVHD) prophylaxis, or G-CSF-primed bone marrow graft and enhanced GVHD prophylaxis. Carefully selecting the donor can help optimize transplant outcomes for recipients of haploidentical donor transplants. Variables usually considered in the donor selection include presence of donor-specific antibodies in the recipient, donor age, donor/recipient gender and ABO combinations, and immunogenic variables, such as natural killer cell alloreactivity or KIR haplotype. Here we provide a comprehensive review of available evidence for selecting haploidentical donors for transplantation, and summarize the recommendations from the European Society for Blood and Marrow Transplantation (EBMT) on donor selection for different transplant platforms.

Impact of conditioning intensity on outcomes of haploidentical stem cell transplantation for patients with acute myeloid leukemia 45 years of age and over

BACKGROUND

T cell-replete haploidentical stem cell transplantation (haplo-SCT) is a valid therapeutic option for adult patients with high-risk acute myeloid leukemia (AML) lacking an HLA-matched sibling or unrelated donor.

METHOD

We retrospectively analyzed the outcomes of 912 AML patients ≥45 years of age who had undergone haplo-SCT with either myeloablative conditioning (MAC; n = 373) or reduced intensity conditioning (RIC; n = 539) regimens.

RESULTS

The median follow-up was 31.1 and 25.7 months for MAC and RIC, respectively. The incidence of relapse and nonrelapse mortality (NRM) were 25.1% versus 28.7% and 31.0% versus 30.3% for MAC and RIC, respectively; 2-year leukemia-free survival (LFS) was 43.9% for MAC versus 41.0% for RIC. In multivariate analysis, the use of MAC versus RIC was not associated with a difference in the outcomes. Results were confirmed in the propensity score-weighted analysis. Disease status and performance status at transplantation were associated with outcomes. Notably, the use of posttransplantation cyclophosphamide was associated with reduced acute graft-versus-host disease (aGVHD) stage III-IV, and NRM and increased overall survival, LFS, and GVHD-free, relapse-free survival. The use of mobilized peripheral blood stem cells was associated with an increased risk of stage II-IV aGVHD.

CONCLUSION

No differences were found between MAC and RIC regimens for haplo-SCT in adults with AML who were ≥45 years of age. The type of GVHD prophylaxis, disease status, and performance status were the major predictors of transplantation outcome. These results may serve as the background for randomized study comparing RIC versus MAC for haplo-SCT in adults with AML.

What the internist should know about stem cell transplant in the elderly patient

Most hematological malignancies are increasing in frequency with age. Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative therapeutic option for patients with malignant and non-malignant hematological diseases. The treatment of elderly patients with advanced hematological malignancies has expanded to include reduced intensity conditioning allo-HCT. Physicians increasingly refer older patients for allo-HCT due to more experience and improved supportive care in allo-HCT. This review article discusses the available data regarding the feasibility, tolerability, toxicity, and effectiveness of allo-HCT in different hematological diseases in the elderly. Over the past decade, utilization and survival after allo-HCT have increased in patients ≥70 years. Selected adults ≥70 years with hematological diseases should be evaluated for transplantation.

Pilot study using post-transplant cyclophosphamide (PTCy), tacrolimus and mycophenolate GVHD prophylaxis for older patients receiving 10/10 HLA-matched unrelated donor hematopoietic stem cell transplantation

Allogeneic SCT for older patients remains challenging at least in part due to graft-versus-host disease (GVHD) and higher non-relapse mortality (NRM). We conducted a prospective pilot study primarily for older patients undergoing matched unrelated donor (MUD) SCT using a reduced-intensity (RIC) melphalan-based conditioning and post-transplant cyclophosphamide (PTCy)-based GVHD prophylaxis with tacrolimus and mycophenolate mofetil. Twenty-two patients (median age 64, IQR 58, 66) underwent RIC MUD SCT for high-risk hematological malignancies including AML/MDS (73%), CML/MPD (18%), and other (10%). Two (9%) patients had early death; the rest (100%) engrafted. After a median follow-up of 17 months, 11 patients were alive and disease-free with an estimated 2-year progression-free (PFS) and overall (OS) survival of 48%. The cumulative incidences of grades 2-4 and 3-4 acute GVHD (aGVHD) at day + 100 and 2-years were 32 and 4%, and 59 and 24%, respectively. No cases of chronic GVHD (cGVHD) were noted. However, late acute GVHD was observed in 6 (27%) patients. In conclusion, RIC MUD SCT with melphalan-based conditioning and PTCy-based GVHD-based prophylaxis for older patients appears effective in controlling relapse. While cGVHD was not seen and early aGVHD appears controllable, a significant proportion developed late aGVHD responsible for higher NRM seen in these patients.